Programming

Some questions regarding exception vs. multiple-thread :

1. there are one main thread and one child thread. the child thread may throw one exception but it doesn't try to catch any exception. in the main thread, it tries to catch excpetion. Can main thread catch the exception that is thrown from child thread?

2. if child tread may throw exception, and neither main tread nor child tread will catch exception. What is the consequence if the child tread really throws one exception. Which tread is crash? Or both crash?


Anyone can help? Thanks.

1. No.

2. Thread *should* exit.

However this all depends on how thread-aware the C++ library is. The best thing to do is for a C++ thread created with pthread_create to have a try/catch(...) block to stop C++ threads trying to unwind through pthread library.

eg

Code:

static void *my_thead(void *arg)
{
    try
    {
       do_funky_stuff();
    }
    catch(...)
    {
    }

    return NULL;
}

Not all platforms support mixing pthread_cleanup_push/pop with C++ local objects.

G++ is appalling with exceptions and threads. For example calling pthread_exit() should cause all local objects to destruct. Sun's Studio11 does this correctly.